Chemistry help please answer all questions need them by 11:30 thank you!

Asolution contains 225 g of sodium chloride, nacl, dissolved in enough water to make a 0.25 l of solution. what is the molarity of the solution? a. 3.88 m, b. 1.03 m, c. 1.5 m, d. 15.5 m

A50.0g sample of liquid water at 0.0 c ends up as ice at -20.0 c. how much energy is involved in this change?

Listenbase your answer to the question on the information below.nuclear radiation is harmful to living cells, particularly to fast-growing cells, such as cancer cells and blood cells. an external beam of the radiation emitted from a radioisotope can be directed on a small area of a person to destroy cancer cells within the body.cobalt-60 is an artificially produced radioisotope that emits gamma rays and beta particles. one hospital keeps a 100.0-gram sample of cobalt-60 in an appropriate, secure storage container for future cancer treatment.which choice represents the correct product for the beta decay of the co-60? fe-60ni-60fe-61ni-61